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Earlier this year, Ann Pettway admitted she snatched a newborn from Harlem Hospital more than two decades ago, and raised the child as her own. Andrew Siff reports. (Published Monday, Jul 30, 2012)

Updated at 6:13 PM PST on Monday, Jul 30, 2012

A woman who snatched a newborn baby from a New York City hospital more than two decades ago and raised her as her own was sentenced Monday to 12 years in prison.

A Manhattan federal court judge sentenced Ann Pettway, 51, to 144 months -- less than the life sentence she could have faced, and less than the 23 years the mother of the kidnapped girl requested.

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"I'm not really satisfied with the sentencing," said Carl Tyson, father of Carlina White, who Pettway scooped up from Harlem Hospital in 1987. "I wasn't able to take my daughter to school... Ann put a scar on me. I didn't have a chance to raise my daughter."

Pettway pleaded guilty to a kidnapping charge in February.

"I would like to apologize," Pettway said Monday. "They may not accept my apology and reject it... but I am deeply sorry... I am here today to right my wrong and ask for forgiveness."

Pettway offered details of the 1987 kidnapping in her February court appearance. She said she took a train from her Connecticut home to Harlem Hospital, where she took Carlina, who had been brought to the emergency room by her parents.

As part of Pettway's plea bargain, prosecutors recommended between 10 and 12½ years in prison.

Carlina's birth mother, Joy White, wept during Pettway's February hearing. "I've lost 23 years of being with my daughter," she said, adding that those decades were filled with pain and heartache.

During the proceeding, Pettway told the court: "I went to the hospital. I took a child. It was wrong."

But she offered no explanation for her action.

White said she encountered Pettway at the hospital on the day her daughter disappeared, dressed like a nurse. "She came up to me and said to me, 'Don't cry. Your daughter is going to be OK.'"

The case was solved by Carlina herself.

As she grew up in Connecticut under another name, the girl became increasingly suspicious of her own identity. Pettway told her she had been given away by a drug addict.

Carlina White said she browsed the website of the National Center for Missing and Exploited Children for clues to her identity. After matching a photo of herself with one on the site, she tracked down her true mother and they reunited in January of 2011. A DNA test confirmed they were mother and child.

Today, they speak every day, Joy White said.

"I love my daughter. She's a beautiful girl," she said, adding that she had kept a picture of her missing baby at her bedside for 23 years.

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